<?php
/**
 * Description of Change
 *
 * @author vadim
 */
abstract class Core_Db_Schema_Change
{
    /**
     * @var Zend_Db_Schema_Adapter_Abstract
     */
    protected $_db;


    function __construct($db)
    {
        $this->_db = $db;
    }

    /**
     * Changes to be applied in this change
     */
    abstract function up();

    /**
     * Rollback changes made in up()
     */
    abstract function down();

}
